A carbon nanotube-coated Cu nanoparticle and its preparation method

Abstract

The present invention discloses a carbon nanotube-coated Cu nanoparticle and a preparation method thereof, belonging to the technical field of composite materials. The method of the present invention includes the following steps: (1) preparation of a Cu-MOF-74 precursor; (2) pressing of the Cu-MOF-74 precursor; (3) preparation of the carbon nanotube-coated Cu nanoparticle. This method uses laser to rapidly prepare the carbon nanotube-coated Cu nanoparticle material in one step. The whole process is directly completed in an air environment without adding any additives or atmosphere environment. The preparation process is short and the process is simple, efficient and convenient. The present invention also provides a carbon nanotube-coated Cu nanoparticle prepared by this method. The material has uniform size and morphology and has good application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials, and in particular to a carbon nanotube-coated Cu nanoparticle and a preparation method thereof. Background Art

[0002] Metal-organic frameworks (MOFs), as a new type of crystalline porous material, are mainly formed by the coordination of metal cations and organic ligands, and the staggered metal cations and organic ligands are arranged in an orderly manner. In recent years, MOFs have received extensive attention due to their unique properties and potential applications in various fields, and thus have been developed and applied rapidly. Using them as precursors to prepare materials of carbon nanotube-coated metal nanoparticles has become a current research hotspot. However, how to use MOFs as precursor materials to obtain carbon nanotube-coated metal nanoparticle materials with uniform size quickly, conveniently and inexpensively has also become a current research difficulty. Summary of the Invention

[0003] In view of the above-mentioned defects of the prior art, in the first aspect of the present invention, a preparation method of carbon nanotube-coated Cu nanoparticles that is fast, convenient and low-cost is provided, including the following steps:

[0004] (1) Preparation of Cu-MOF-74 precursor:

[0005] Copper nitrate trihydrate and phthalic acid react in a solution environment and at a certain temperature. After the reaction, solvent replacement and drying are carried out to obtain a powdery nanowire-type Cu-MOF-74 precursor.

[0006] (2) Pressing of Cu-MOF-74 precursor:

[0007] Open holes in the metal foil to form an accommodating cavity, clamp the metal foil with a transparent carrier sheet, and lay the Cu-MOF-74 precursor in the accommodating cavity. Then, after compaction and fixation, a precursor tablet is obtained.

[0008] (3) Preparation of carbon nanotube-coated Cu nanoparticles:

[0009] The Cu-MOF-74 precursor in the accommodating cavity of the precursor tablet is continuously scanned by laser to obtain carbon nanotube-coated Cu nanoparticles.

[0010] Due to the action of the laser, instantaneous high temperature and high pressure will be generated in the pressing accommodating cavity, causing the Cu-MOF-74 precursor to instantaneously react and change from reddish-brown to black, and then carbon nanotube-coated Cu nanoparticles are obtained.

[0011] Preferably, the specific method of step (1) is as follows: Dissolve copper nitrate trihydrate in N,N-dimethylformamide to obtain solution I; dissolve phthalic acid in N,N-dimethylformamide to obtain solution II; add solution II to solution I, mix evenly, and react at a certain temperature. After the reaction, perform solvent replacement and drying to obtain a powdery nano-linear Cu-MOF-74 precursor.

[0012] More preferably, in the preparation process of solution I, the dosage of copper nitrate trihydrate is 0.5 - 2.0 g, and the dosage of N,N-dimethylformamide is 5 - 20 mL; in the preparation process of solution II, the dosage of phthalic acid is 0.36 - 1.44 g, and the dosage of N,N-dimethylformamide is 5 - 20 mL.

[0013] Preferably, in step (1), the reaction temperature is 80 - 100 °C, and the reaction time is 12 - 24 h.

[0014] Preferably, in step (1), the solvent replacement uses at least one of absolute ethanol and N,N-dimethylformamide.

[0015] Preferably, the specific method of step (2) is as follows: Prepare a transparent slide and a metal foil. Punch the metal foil to form a receiving cavity, place the metal foil on the surface of the transparent slide, then evenly lay the Cu-MOF-74 precursor in the receiving cavity, cover it with the transparent slide, compact it, and fix the transparent slide to obtain a precursor tablet.

[0016] Preferably, in step (2), the metal foil is one of copper foil, iron foil, and nickel foil.

[0017] Preferably, the specific method of step (3) is as follows: Continuously scan the Cu-MOF-74 precursor in the receiving chamber of the precursor tablet by laser. After scanning one side of the precursor tablet, repeat the above operation to scan the other side of the precursor tablet to obtain carbon nanotube-coated Cu nanoparticles.

[0018] Preferably, in step (3), the power of the laser is 3 - 8 W, and the speed of the continuous scanning is 60 - 90 mm / s.

[0019] In the second aspect of the present invention, the present invention provides a carbon nanotube-coated Cu nanoparticle, and the carbon nanotube-coated Cu nanoparticle is prepared by the preparation method of the first aspect of the present invention.

[0020] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0021] The present invention provides a preparation method of carbon nanotube-coated Cu nanoparticles. This method uses laser to rapidly prepare carbon nanotube-coated Cu nanoparticle materials in one step. The whole process is directly completed in an air environment without adding any additives or atmosphere environment. The preparation process is short and the process is simple, efficient and convenient.

[0022] The present invention provides a carbon nanotube-coated Cu nanoparticle, and the material has uniform size and morphology. Description of the Drawings

[0023] Figure 1 is a partial process schematic diagram of the preparation method of the carbon nanotube-coated Cu nanoparticle of the present invention;

[0024] Figure 2 is the polycrystalline X-ray diffraction (PXRD) pattern of the Cu-MOF-74 precursor in Example 1;

[0025] Figure 3 is the scanning electron microscope (SEM) image of the carbon nanotube-coated Cu nanoparticle in Example 1;

[0026] Figure 4 is the transmission electron microscope (TEM) image of the carbon nanotube-coated Cu nanoparticle in Example 1;

[0027] Figure 5 Among them, the left figure is the transmission electron microscope (TEM) image of the carbon nanotube-coated Cu nanoparticle in Example 1, and the right figure is the statistical result of its particle size;

[0028] Figure 6 Among them, the left figure is the transmission electron microscope (TEM) image of the carbon nanotube-coated Cu nanoparticle in Example 1, and the right figure is its selected area electron diffraction (SAED) pattern. Detailed Embodiments

[0029] The present invention will be further described below by way of examples, but the present invention is not limited to the scope of the described examples. For the experimental methods without specific conditions in the following examples, they are carried out according to conventional methods and conditions, or selected according to the product specifications.

[0030] Example 1

[0031] Preparation method of carbon nanotube-coated Cu nanoparticle:

[0032] (1) Preparation of Cu-MOF-74 precursor:

[0033] Weigh 1.05 g of copper nitrate hydrate and dissolve it in 10 mL of N,N-dimethylformamide to obtain Solution I. Weigh 0.72 g of phthalic acid and dissolve it in 10 mL of N,N-dimethylformamide to obtain Solution II. Then slowly add Solution II to Solution I and mix evenly. Put the resulting mixed solution into a high-temperature furnace, heat it to 80 °C and keep it for 24 h to complete the reaction. After the reaction is completed, let it cool naturally to room temperature. Replace the obtained product with anhydrous ethanol and N,N-dimethylformamide three times each. The obtained blue powder is dried in vacuum to obtain a powdery nano-linear Cu-MOF-74 precursor.

[0034] (2) Tablet pressing of Cu-MOF-74 precursor:

[0035] As Figure 1 shown, prepare two glass slides as transparent carriers, and prepare another copper foil with a thickness of 0.2 mm. Punch a 10-mm round hole in the copper foil with a punching machine. Then place the copper foil in the center of one of the glass slides. Uniformly lay the prepared Cu-MOF-74 precursor in the center of the hole in the copper foil, and then cover it with another glass slide. In order to uniformly lay the Cu-MOF-74 precursor in the hole, knead the two glass slides by hand and press them tightly. Finally, fix both ends of the glass slide with transparent tape to obtain a precursor tablet.

[0036] (3) Preparation of carbon nanotube-coated Cu nanoparticles:

[0037] Place the obtained precursor tablet under an IPG laser, set the power of the laser to 6 W and the scanning speed to 70 mm / s. Then continuously scan the Cu-MOF-74 precursor in the middle of the glass slide with the IPG laser. After scanning one side, scan the other side with the same laser parameters to obtain carbon nanotube-coated Cu nanoparticles.

[0038] Example 2

[0039] Preparation method of carbon nanotube-coated Cu nanoparticles:

[0040] (1) Preparation of Cu-MOF-74 precursor:

[0041] Weigh 0.5 g of copper nitrate hydrate and dissolve it in 5 mL of N,N-dimethylformamide to obtain Solution I. Weigh 0.36 g of phthalic acid and dissolve it in 5 mL of N,N-dimethylformamide to obtain Solution II. Then slowly add Solution II to Solution I and mix evenly. Put the resulting mixed solution into a high-temperature furnace, heat it to 100 °C and keep it for 12 h to complete the reaction. After the reaction is completed, let it cool naturally to room temperature. Replace the obtained product with anhydrous ethanol and N,N-dimethylformamide three times each. The obtained blue powder is dried in vacuum to obtain a powdery nano-linear Cu-MOF-74 precursor.

[0042] (2) Pressing of the Cu-MOF-74 precursor

[0043] As Figure 1 shown, prepare two glass slides as transparent carriers, and another 0.2 mm thick iron foil. Punch a 10 mm round hole in the iron foil with a punching machine. Then place the iron foil in the center of one of the glass slides, evenly lay the prepared Cu-MOF-74 precursor in the center of the hole in the iron foil, and then cover it with another glass slide. To evenly lay the Cu-MOF-74 precursor in the hole, knead the two glass slides by hand and press them tightly. Finally, fix both ends of the glass slide with transparent tape to obtain the precursor tablet

[0044] (3) Preparation of carbon nanotube-coated Cu nanoparticles

[0045] Place the obtained precursor tablet under an IPG laser, set the power of the laser to 3 W, and the scanning speed to 60 mm / s. Then continuously scan the Cu-MOF-74 precursor in the middle of the glass slide with the IPG laser. After scanning one side, scan the other side with the same laser parameters to obtain carbon nanotube-coated Cu nanoparticles

[0046] Example 3

[0047] Preparation method of carbon nanotube-coated Cu nanoparticles

[0048] (1) Preparation of the Cu-MOF-74 precursor

[0049] Weigh 2.0 g of copper nitrate trihydrate and dissolve it in 20 mL of N,N-dimethylformamide to obtain Solution I. Weigh 1.44 g of phthalic acid and dissolve it in 20 mL of N,N-dimethylformamide to obtain Solution II. Then slowly add Solution II to Solution I and mix evenly. Put the obtained mixed solution into a high-temperature furnace, heat it to 90 °C and keep it for 18 h to complete the reaction. After the reaction, cool it naturally to room temperature. Replace the obtained product with anhydrous ethanol and N,N-dimethylformamide three times each. The obtained blue powder is dried in vacuum to obtain a powdery nanowire-type Cu-MOF-74 precursor

[0050] (2) Pressing of the Cu-MOF-74 precursor

[0051] As Figure 1As shown in the figure, prepare two glass slides as transparent slides, and also prepare a copper foil with a thickness of 0.2 mm. Punch a 10-mm round hole in the nickel foil with a punching machine. Then place the nickel foil in the center of one of the glass slides, evenly lay the prepared Cu-MOF-74 precursor in the center of the nickel foil hole, and then cover it with another glass slide. In order to evenly lay the Cu-MOF-74 precursor in the hole, knead the two glass slides by hand and press them firmly. Finally, fix both ends of the glass slide with transparent tape to obtain a precursor tablet.

[0052] (3) Preparation of carbon nanotube-coated Cu nanoparticles:

[0053] Place the obtained precursor tablet under an IPG laser, set the laser power to 8 W, and the scanning speed to 90 mm / s. Subsequently, continuously scan the Cu-MOF-74 precursor in the middle of the glass slide with the IPG laser. After scanning one side, scan the other side with the same laser parameters to obtain carbon nanotube-coated Cu nanoparticles.

[0054] Example 4

[0055] Use a polycrystalline X-ray diffractometer (PXRD) to characterize the phase of the Cu-MOF-74 precursor material prepared in Example 1. The X-ray source used in PXRD is Cu target Kα. The scanning speed used is 2θ = 5° / min, and the scanning range is 5 - 80°. The results are shown in Figure 2 . It can be seen from Figure 2 that the characteristic peaks are consistent with those of Cu-MOF-74, proving that the Cu-MOF-74 metal-organic framework material has been synthesized.

[0056] Observe the microscopic morphology of the carbon nanotube-coated Cu nanoparticles prepared in Example 1 by scanning electron microscopy (SEM). The results are shown in Figure 3 . It can be seen from Figure 3 that the carbon nanotubes and Cu nanoparticles have uniform sizes and morphologies, and the Cu nanoparticles are coated with carbon nanotubes.

[0057] Further observe the microscopic morphology of the carbon nanotube-coated Cu nanoparticles prepared in Example 1 by transmission electron microscopy (TEM). The results are shown in Figure 4 . Figure 4 It further proves that the Cu nanoparticles are coated with carbon nanotubes.

[0058] Observe the microscopic morphology of the carbon nanotube-coated Cu nanoparticles prepared in Example 1 by transmission electron microscopy (TEM). Randomly select 150 nanoparticles in the selected area to statistically analyze the size of the Cu nanoparticles in the TEM image, and at the same time characterize it with a selected area electron diffraction pattern (SAED) in this area. It can be seen from Figure 5It can be seen from the particle size statistics in the right figure that the Cu nanoparticles have uniform size and morphology, and the average size is about 27 nm. From Figure 6 The lattice fringes can be clearly seen from the left figure and its upper right attached figure. By measuring the interplanar spacing, it is found that the spacing is 0.21 nm, which highly coincides with the crystal plane of Cu; from Figure 6 It can be found from the right figure that the diffraction rings belong to the 311, 220, 200, and 111 planes of Cu, further proving that the synthesized nanoparticles are Cu nanoparticles.

[0059] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative work. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should be within the protection scope determined by the claims.

Claims

1. A preparation method of carbon nanotube-coated Cu nanoparticles, characterized in that, It includes the following steps: (1) Preparation of Cu-MOF-74 precursor: Copper nitrate trihydrate and phthalic acid react in a solution environment at a certain temperature. After the reaction, solvent replacement and drying are carried out to obtain a powdery nanowire-shaped Cu-MOF-74 precursor; (2) Tabletting of Cu-MOF-74 precursor: Prepare a transparent slide and a metal foil. The metal foil is punched to form a receiving cavity. Place the metal foil on the surface of the transparent slide. Then, evenly lay the Cu-MOF-74 precursor in the receiving cavity, cover it with the transparent slide, fix the transparent slide after compaction to obtain a precursor tablet; (3) Preparation of carbon nanotube-coated Cu nanoparticles: Continuously scan the Cu-MOF-74 precursor in the receiving cavity of the precursor tablet by laser to obtain carbon nanotube-coated Cu nanoparticles.

2. The method according to claim 1, wherein The specific method of step (1) is as follows: Dissolve copper nitrate trihydrate in N,N-dimethylformamide to obtain solution I; dissolve phthalic acid in N,N-dimethylformamide to obtain solution II; add solution II to solution I, mix evenly and react at a certain temperature. After the reaction, solvent replacement and drying are carried out to obtain a powdery nanowire-shaped Cu-MOF-74 precursor.

3. The method according to claim 2, wherein: In the preparation process of solution I, the amount of copper nitrate trihydrate used is 0.5 - 2.0 g, and the amount of N,N-dimethylformamide used is 5 - 20 mL; in the preparation process of solution II, the amount of phthalic acid used is 0.36 - 1.44 g, and the amount of N,N-dimethylformamide used is 5 - 20 mL.

4. The method according to claim 1, characterized in that: In step (1), the reaction temperature is 80 - 100 °C, and the reaction time is 12 - 24 h.

5. The method according to claim 1, characterized in that: In step (1), the solvent replacement uses at least one of anhydrous ethanol and N,N-dimethylformamide.

6. The method according to claim 1, characterized in that: In step (2), the metal foil is one of copper foil, iron foil, and nickel foil.

7. The method according to claim 1, characterized in that The specific method of step (3) is as follows: Continuously scan the Cu-MOF-74 precursor in the receiving cavity of the precursor tablet by laser. After one side of the precursor tablet is scanned, repeat the above operation to scan the other side of the precursor tablet to obtain carbon nanotube-coated Cu nanoparticles.

8. The method according to claim 1, characterized in that: In step (3), the power of the laser is 3 - 8 W, and the speed of the continuous scan is 60 - 90 mm / s.

9. A carbon nanotube-coated Cu nanoparticle, characterized in that: It is prepared by the method described in any one of claims 1 - 8.

Images